HYDROFORMYLATION OF 2,3-DIHYDROFURANS AND 2,5-DIHYDROFURANS IN THE PRESENCE OF A HOMOGENEOUS CATALYTIC COMPLEX BASED ON ACACRH(CO)2 MODIFIED WITH DIFFERENT PHOSPHITES

Effective rhodium catalytic systems have been selected for the hydrofo rmylation of 2,3- and 2,5-dihydrofurans based on AcAcRh(CO)2 + 9L, whe re L is ,5-tetra-tert-butyl-1,1-biphenyl-2,2-diylphosphite (organophos phite) or etriolphosphite. The hydroformylation of 2,3-dihydrofuran (D HF) proceeds regioselectively in relation to 2-formyltetrahydrofuran i n the case of organophosphite and in relation to 3-formyltetrahydrofur an in the case of etriolphosphite. In the latter case, the increase in the 3-formyltetrahydrofuran yield is caused by the isomerization of 2 ,3-DHF to 2,5-DHF. 2,5-Dihydrofuran has a retarding effect on the hydr oformylation of 2,3-DHF. A quantum-chemical and kinetic study was made of the formation of isomeric aldehydes during the hydroformylation of 2,3-DHF.